The Independent reports that a member of the Treasury Select Committee has said that the company's approach to tax was "entirely improper and immoral", and he expects the firm to be called before MPs next year.

Google, which has more than 1,500 staff based in the UK, has been criticized for moving most of the money it makes into the tax haven of Bermuda, meaning it only pays a minimum to the Treasury.

Due to current makeup of UK corporation tax laws, the US search firm can pay more but only if it voluntarily agrees to do so.

Campaign group 38 Degrees has now launched a protest petition against the firm's practices, which is already 45,178 signatures into its 50,000 target.

Text alongside the petition says: "Dear Google. It's time for Google to pay its fair share of tax.

"There's nothing responsible about only paying £6 million in UK tax on hundreds of millions of pounds of revenue. Please do the right thing."

John Mann MP, a member of the Treasury Select Committee, said that he had discussed with his colleagues about investigating tax avoidance schemes and expects Google to be called in Easter.

Discussing Google's activity, which is not illegal, Mann said: "It is entirely immoral, this is a company avoiding its obligations and we are letting them get away with doing it.

"I think it would be highly appropriate to pull a Google executive in front of the Committee to justify their failure to pay proper taxes, we would be looking at covering the issue in this parliamentary session, so before Easter, realistically. Whether it is illegal or immoral, the British tax payer loses out. Google is one of the big ones but there are others."

Google operates a system in which its Irish subsidiary employs Google UK as an agent, meaning the proceeds of UK sales end up in Ireland, where the tax rate is lower. A commission of around 10% is paid back to the British business, which is then taxable.

Google Ireland in turn pays most of the money it makes to the search giant's Bermuda firm, meaning most of the earnings end up in the tax haven. This is a totally legal process.

Speaking last year, Google's executive chairman Eric Schmidt said that the firm could pay more tax in Britain, but only if it voluntarily agreed to the increase.

"We could pay more tax but we would have to do so voluntarily. There are lots of benefits to [being in Britain]," he said.

"It's very good for us, but to go back to shareholders and say, 'We looked at 200 countries but felt sorry for those British people so we want to [pay them more]'... there is probably some law against doing that."

Mann, the Labor MP for Bassetlaw, told The Independent that the Bermudan government must take a firmer stance on tax avoidance schemes, particularly as it is a British dependency.

"This sort of scheme is running, meanwhile we are providing a legal base and defense for Bermuda because it is a British dependency," he said.

"Firstly, we should be ensuring first of all that this is not possible across the EU. There is no point being in if you can tax dodge.

"Secondly, if Bermuda or any other British dependency wants our help with defense, then it should stop operating this sort of tax policy. We are paying twice because we are paying for Bermuda."

In a statement, a Google spokesman said: "We make a substantial contribution to the UK economy through local, payroll and corporate taxes.

"We also employ over a thousand people, help hundreds of thousands of businesses to grow online and invest millions supporting new tech businesses in East London. We comply with all the tax rules in the UK."